This island was given to Tycho Brahe, for his life, by Frederick II., King of Denmark, together with a large pension. And on August 8, 1576, this great astronomer laid the foundation of his famous observatory, or castle, called Uranienburg, where he resided twenty-one years. He died at Prague, to which city he went on the invitation of the Emperor Rodolphus II. in 1601, aged 55.